The present invention relates to a device and method for treating all types of parts, in particular bones, organs, etc. of the human/animal body, and which includes a housing, a tool associated to the housing, and an actuation unit that causes a relative movement between the housing and the tool.
For a surgical manipulation of bones, in particular in orthopedic surgery, it has already become common practice to use passive navigators, which assist a user in the orientation of the tool on the patient and in a precise operative planning of the surgery. However, all operational steps are performed by the users themselves.
In these navigation systems, the computer navigated tools do not automatically reach the desired position, because they are opposed by muscle tremor and involuntary transient movements of the operator during the operation. Accordingly, the pre-operative planning is put into action with imperfections.
In particular in the case of endoprothesis of the hip and knee as well as corrective surgery of the hip joint and replacement of the anterior cruciate ligament of the knee, it is common to use robots, which automatically perform as active navigators on the patient surgical steps that may be previously programmed at a work station or directly in the operating room.
A disadvantage of such systems is on the one hand the prolonged duration of the operation, and on the other hand the very high costs of purchase and upkeep as well as the additional floor space requirements for such systems. Moreover, when using a robot, many surgeons subjectively miss a process control by reason of events which may occur on the operating table.
A device of the generic type is disclosed in DE 197 00 402 C2. The appliance described therein makes it possible to compensate to the greatest extent possible involuntarily occurring trembling of the hands (tremor), when manually working on fine structures. This compensation of the muscle tremor is of great importance in particular in microsurgery. In this connection, the appliance mounts acceleration and angular speed sensors that supply a mechanical or electrical signal which correlates with the movement of the appliance. These sensor signals are amplified in a first step. Subsequently, they are analyzed with respect to frequency, amplitude, and direction or acceleration of the tool. It is thus possible to evaluate undesired movements and differentiate them from intended movements. With reference to the data, it is possible to activate the actuators such that they cause relative movements of the movable section for compensating an undesired deflection of the handheld section.
While the known device permits excluding the muscle tremor from the tool movement to a large extent, it is problematic in that positioning of the tool cannot be controlled in a programmable fashion, but must be performed by hand. When a surgeon applies the operating tool, for example, a drill, in a wrong location or in a wrong angular position, the known device will not detect this error, and consequently will not correct it.
It is therefore an object of the present invention to provide a device and method of the initially described type for treating all types of body parts, in particular bones, organs, etc. of the human/animal body, which allows the user significant control over the process and a rapid and reliable work routine, while making use of specific possibilities of robotics and computer assisted navigation.